Thermal timing mechanism



19, 1943. R. $ARDESON THERMAL TIMING MECHANISM Filed May 9, 1958 5 Sheets-Sheet 1 3mm R obert Sardeson Oct. 19,1943. R. SARDESON THERMAL TIMING MECHANISM Filed May 9, 1938 5 Sheets-Sheet 2 In sulati on JIWWM Q a i ainllilliz Oct. 19,1943. R. SARDESON THERMAL TIMING MECHANISM 5 Shets-Sheet 5 Filed May 9, 1938 W M w f- 1 m @WW W% E WW In sulaoi on I In sulat'mon 3mm Robert $axfde$on Och 1943. R. SARDESON 2,332,171

THERMAL TIMING MECHANI SM Filed May 9, 1938 5 Sheets-Sheet 4 Insulation MYL Loi

Insulation 55 w m Robert Sardeson THERMAL TIMING MECHANISM Robert Sardeson, Minneapolis, Minn., assignor to Harold C. Genter, Miami Beach, Fla.

Application May 9, 1938, Serial No. 206,899

27 Claims.

My invention relates to thermal timing mechanisms and has for an object to provide an extremely simple and practical timing mechanism so constructed and arranged as to be capable of successive operations or cycles without the need i or intervening cooling periods.

Another object of the invention resides in providing a thermal timing mechanism utilizing a single thermally responsive member and a single heater therefore, said timing mechanism being capable of performing its controlling or cycle measuring function repeatedly without need for cooling periods intervening between complete cycles.

Another object of the invention resides in providing a thermal timing mechanism in which the duration of time greatly exceeds that required for the heating or cooling of the thermally responsive member during a single cycle.

A still further object of the invention resides in providing a thermal timing mechanism in which the controlled device is actuated as the result of a number of successive deflections of the thermally responsive member.

An object of the invention resides in providing a thermal timing mechanism in which a thermally responsive member is successively heated at different portions of the same.

A still further object of the invention resides in providing a thermal timing mechanism in which an elongated thermally responsive member is employed which is successively heated at different localities throughout the length thereof to procure localized deflections of said member.

A feature of the invention resides in heating said thermally responsive member at one locality and thereafter heating said thermally responsive member at another locality while cooling the same at the first locality.

An object of the invention resides in providing a thermal timing mechanism having an elongated thermally responsive member which is moved past a fixed heater and successively heated thereby at difierent localities.

Another object of the invention resides in making said thermally responsive member continu- 0115 so that the same may be caused to repeatedly operate upon the completion of its cycle without re-setting.

A feature of the invention resides in constructing said thermally responsive member either in the form of a rectilinear ribbon, a hoop, a disc or an annulus so as to provide portions of the same arranged in predetermined order with respect to other portions, whereby one or more heaters may be utilized to successively heat the successive portions while previously heated portions are being cooled.

Another object of the invention resides in providing means tending to urge movement of the thermally responsive member away from the heater and in providing a stop mechanism controlled by the deflections of said member for releasing said means to procure movement of said member.

Other objects of the invention reside in the novel combination and arrangement of parts and in the details of construction hereinafter illustrated and/or described.

In the drawings:

Fig. 1 is a plan view of a thermal timing mechanism illustrating an embodiment of my invention.

Fig. 2 is a side elevational view of the structure shown in Fig. 2.

Fig. 3 is a view similar to Fig. 2 of a portion of the structure shown therein and viewed from the opposite side of the mechanism.

Fig. 4 is a fragmentary longitudinal elevational sectional view taken on line 44 of Fig. 1.

Fig. 5 is a cross sectional view taken on line 5--5 of Fig. 3.

Fig. 6 is a front elevational view of a modification of the invention.

Fig. '7 is a side elevational view of the structure shown in Fig. 6.

Fig. 8 is a plan sectional view taken on line 8-8 of Fig. 6.

Fig. 9 is a front elevational view of still another form of the invention.

Fig. 10 is a rear elevational view of the structure shown in Fig. 9.

Fig. 11 is a side elevational view of the structure shown in Fig. 9 and viewed from the left side thereof.

Fig. 12 is a plan view of the structure shown in Fig. 9.

My invention as shown in the drawings may be used for various purposes such as for controlling the operation of dilierent devices and mechanisms requiring operation or actuation or cessation or termination of operation upon the lapse of a predetermined length of time. Such devices may include alarms and signals, devices requiring deferred operation and may also include electric toasters, wailie irons, egg cookers and numerous'similaf'devicfilficlifetiuire discontinuation of operation or change in the mode of operation after the lapse of the desired time. In view of this fact, the application of the invention has not been disclosed in detail although it readily can be comprehended that the invention may be used in place of any of the previously invented timing devices now used for the same or similar purposes.

The form of the invention shown in Figs. 1 to inclusive, comprises a base l0, constructed of sheet metal which is formed with flanges H and I2 extending upwardly therefrom. The base I0 is elongated in form and at one end thereof is provided with an upright |3 which is likewise constructed with flanges M which are secured to or butt against the flanges II and l2 and resist movement of the upright It in one direction with ligeference to the longitudinal extent of the said ase.

At the end of the base It, opposite the upright |3, the flanges H and I2 are drilled to form bearings for two transversely extending shafts I1 and I8 which are parallel to one another and b to the base l0. These shafts are situated the same height above the base. The shaft I'I carries two flanged wheels l9 while the shaft l8 similarly carrie two flanged wheels 2|. Riding upon these wheels is an elongated thermally responsive member 22 which consists of a strip of himetal or some other suitable material adapted to bow or deflect when heat is applied to the ame.

The thermally responsive member 22 is urged to travel to the left, as viewed in Figs. 1 and 2, by means of a tension coil spring 23, which is hooked at one end to the upright I3 and at the other end to the said thermally responsive member. exerted by the same is in the direction of length of said thermally responsive member, whereby said member may ride upon the wheels l9 and 2| as said member is moved.

The thermally responsive member 22 is constructed with a number of holes 24 arranged one after the other to provide bars 25 therebetween which serve as gear teeth and which together form a rack extending along the thermally responsive member. These gear teeth mesh with the teeth 25 of a sprocket wheel 21 which is rigidly secured to the shaft l1, so that said sprocket wheel and shaft rotate and the bi-metal strip 22 moves lengthwise coincidentally under the influence of spring 23. The pitch diameter of the sprocket wheel 21 is substantially equal to the diameters of the wheels I9 so that the teeth thereof may mesh with the teeth 25 of the thermally responsive member 22 while the same is riding upon the wheels IS. The sprocket wheel 21 forms part of a stop device which cooperates with the teeth 25 which serve as stops for holding the thermally responsive member from movement.

Movement of the following manner.

shaft I1 is controlled in the Attached to this shaft is an escapement wheel 28 which has a number of teeth 29 extending outwardly therefrom. Cooperating with the escapement wheel 28, is a crown piece 3| which carries a pallet 32a adapted to engage the various teeth 29. This crown piece is pivoted by means of a pivot 33 to an upright formed on the flange II.

The crown piece 3| is moved by means of a lever 35 which is pivoted by means of a pivot 35 to an upright 31 formed on the flange This lever has a stud 38 extending outwardly therefrom which is slldably and rotatably mounted in a slot 39 formed in an arm 4| issuing from the crown piece 3|. As the lever 35 swings up and This spring is so positioned that the pull down the crown piece 3| is oscillated about the pivot 33 and the pallet 32a. caused to successively engage the teeth 29 of the escapement wheel 28, thereby allowing the said wheel to rotate in a step-by-step fashion as the lever 35 oscillates.

The lever 35 has secured to it a stud 42 which rotatably supports a roller 43. This roller is adapted to ride upon the upper surface of the thermally responsive member 22 and is arranged between the marginal portion of the same and the row of holes 24. A tension coil spring 44 hooked to the flange H and to the stud 38 normally draws lever 35 downwardly maintaining roller 43 in contact with the upper surface of the thermally responsive member 22 and thereby also maintaining said member in position upon the wheels |9 and 2|.

Roller 43 is disposed substantially midway between the two shafts l1 and I8. Immediately below that portion of the bi-metal strip on the edge of which roller 43 bears is an electric heater 45 which consists of an open coil of resistance wire attached to an insulating support 46. This support is attached to the flange |2. A suitable source of electric current is connected to this heater and maintains the same heated at all times during the operation of the invention.

Attached to the end of the thermally responsive member 22 is a cam 48. This cam is adapted to engage a cam surface 49, formed on the end of a lever 5|. Lever 5| is pivoted at 52 to the flange H and is provided with an arm 53 extending upwardly therefrom. Pivoted to this arm is a link 54 which goes to the mechanism controlled by the invention. Inasmuch as my improved thermal timing mechanism may be used with any appropriate type of device, such as previously brought out, the method of connecting the ame to such devices has not been shown in detail in this application.

The operation of my invention is as follows: Before the heater 45 is energized the-various parts are moved to the position shown in Fig. 3 in which pallet 32a is in engagement with one of the teeth 29. As soon as the heater 45 is energized, heat is transmitted to the thermally responsive member 22 from below the same and when the same reaches a sufficient temperature the said member bows or deflects in an upward direction. Inasmuch as the roller 43 rests upon the thermally responsive member 22 immediately above the heater 45, this roller is elevated and the lever 35 swung upwardly. This oscillates the crown piece 3|, causing the pallet 32a to be disengaged froin the tooth of wheel 28. The then position of the parts is shown in Fig. 4. As will be apparent, withdrawal of pallet 32a from its previous engagement with one of the teeth 29 is shown in Fig. 3, freeing the bi-metal strip to move lengthwise under the influence of spring 23, the bi-metal, by reason of its engagement with the teeth 26 of sprocket wheel 21 thereby causing shaft l1 and escapement wheel 28 to rotate. Thus the pallet 32a. lever 35 and roller 43 together constitute a latch mechanism which, acting through the escapement wheel and sprocket wheel 21 normally holds the bi-metal against movement relatively to the heater; which latch mechanism is released, to permit such movement, in response to the local heating and deflection of that portion of the bi-metal which is subject to the influence of the heater 45.

Movement of the bi-metal strip remove the heated and deflected portions of it away from the heater and out from under roller 43, so that fl till-stilt \SM,

as the adjacent non-heated and non-distorted portion of the strip advances, the roller 43 is lowered again and pallet 32a is moved back into position to engage the next approaching tooth 29 of wheel 28. When such engagement occurs, movement of the parts is arrested; the portion of the bi-metal strip which is then over the heater is heated, warps, raises roller 43, and the above described sequence is repeated. The heating and deflecting of successive portions or zones of the bi-metal strip continues until the cam 48 engages the cam surface 49 of lever which terminates movement of the thermally responsive member 22 and which operates the link 54 in a manner to perform the function for which the device is intended. In re-setting the mechanism the thermally responsive member 22 may be manually moved toward the right as shown in Figs. 1 and 2. Such movement is accommodated by the escapement device, the teeth of which are shaped to permit of reverse movement of the thermally responsive member controlled thereby. It will be noted that as each fresh portion of the thermally responsive member is heated the previously heated portion is being cooled so that when the cam 48 reaches cam surface 49 the end of the thermally responsive member first acted upon is sufliciently cooled so that the mechanism is ready to be reset without delay. If the surrounding temperature or the interval between the successive operations of the mechanism is such that the bi-metal i quite cool when the cycle of operations commences, the mechanism serves as a constant timer, 1. e. the time consumcd by each complete cycle is constant; whereas if the bi-metal is not quite cool when any cycle commences, then, obviously, less heat will be required to be put into the bi-metal to deflect it and the cycle will consume a correspondingly shorter time. It will be readily comprehended that the device can be manually adju ted to operate for a shorter length of time in the resetting of the device by merely moving the thermally responsive member toward the right a distance less than the maximum distance of travel thereof.

In Figs. 6, 7 and 8 I have shown a modification of the invention in which the thermally responsive member instead of being a flat strip is constructed in the form of a continuous hoop and in which re-setting of the devices become unnecessary when the mechanism has performed the desired function.

The mechanism shown in Figs. 6, '7 and 8 comprises a base 55 to which is attached an upright 56. This upright is constructed of sheet metal which is bent to provide a flange 51 issuing therefrom, which flange serves to stiffen and re-inforce the same. The upright 56 may be attached to the base 55 by welding or otherwise as desired.

Attached to the upright 56, intermediate the ends thereof, is a stud 58 on which is rotatably mounted a ratchet wheel 59 and an arm 60. A bolt 6| extending through the stud 58 holds the two parts in proper position upon said stud. Arm 60 has pivoted to it a pawl 62 which engage the teeth 63 of ratchet wheel 59 and procures movement thereof in one direction as the arm 60 is oscillated. Pawl B2 is urged into engagement with the ratchet teeth 63 by means of a coil spring 64 acting between said pawl and the arm 60. To prevent reverse movement of the ratchet wheel 59, another pawl H5 is employed which is pivoted on a post H6 secured to the upright 56. Pawl H5 has an arm H! to which is attached a tension coil spring H8. This spring is hooked on another post H9 which is also secured to the upright 56. This spring holds the pawl H5 in engagement with the ratchet wheel 59 as shown in Fig. 6 and prevents reverse movement of the same when the arm 68 is traveling in aclockwise direction.

Encircling the stud 58 is a hoop 65 constructed of a thermally responsive material such as a strip of bi-metal. This hoop constitutes the thermally responsive member of this form of the invention which is continuous in extent and is so arranged that, when heated, the same deflects outwardly. The hoop 65 is guided for rotation about the axis of the stud 58 as a center by means of two flanged guide rollers 66 which are pivoted on stud 61 secured to the upright 56. The thermally responsive member 65 is further guided by means of two plates HI which are held in spaced relation by means of a sleeve H2 and a washer H3 which plates are supported through a bolt H4 extending through said sleeve and washer and bolted to the upright 56. These plates permit the hoop 65 to rotate but confine the movement thereof to a plane at right angles to the axis of the stud 58.

Between the two studs 61 and attached to the upright 56 is an insulated shelf 8 which supports a heater 69, similar to the heater 45, previously referred to. This heater is adapted to heat the portion of the hoop 65 between the rollers 66 and to cause the same to deflect upwardly.

Situated above the hoop 65 is a lever H. Lever 'H is pivoted on a pintle 12 which is secured to the upright 56. The lever H supports a roller I3 rotatably mounted on a stud 14 which is secured to said lever at a position so that the roller 12 may engage the outer periphery of the thermally responsive member 65 at a locality substantially midway between rollers 66. At the end of the lever H i a contact bar 15 which forms one of the switch element of a switch 16. The switch 16 further includes two contacts 11 which are adapted to be connected together by means of the bar 15 when the lever H is elevated. The contacts 11 are mounted on an insulated support 18 which is secured to a bracket I9 formed on the upright 56. It will thus become readily apparent that, when the heater 69 heats the hoop 65 to a sufficient degree of temperature, the portion of said hoop engaging the roller 13 is bowed outwardly and the lever H swung upwardly until the contact bar 15 engages the contact 1'! and closes switch 16.

The hoop forming the thermally responsive member 65 is caused to rotate about the axis of the stud 58 by means of the following construction: At the uppermost portion of the upright 55 is a solenoid 8| which is attached to said upright by means of brackets 82 and screws 83. This solenoid is connected by means of suitable conductors, not shown in the drawings, to a circuit including a source of electromotive form and the switch 16. Whenever the switch 16 is closed, the solenoid 8| becomes energized. Solenoid 8| has a sliding plunger 84 which is normall urged outwardly by means of a compression coil spring 85 which encircles the same and which is seated at its outer end against a collar 86 formed on said plunger. Pivoted to the end of the plunger at 81 is a link 88 which in turn is pivoted to a stud 89 fast on the end of the arm 60. This stud also rotatably supports a roller 91 which engages the outer surface of the thermally responsive member 65. Pivoted on the arm 68 at 92 is a dog 93 which is adapted to engage the inner surface of the hoop forming the thermally responsive member 65. This dog has a wedgedshaped surface 94 which exerts a wedge action upon the hoop 65 forcing the same against the roller 9|. When the plunger 84 of solenoid 8I is moved inwardly, arm 60 is swung in a counterclockwise direction. This causes the surface 94 of dog 93 to wedge against the inner surface of the hoop 65 and the hoop is caused to travel with the said dog and to be given a partial rotation with respect to the axis thereof in a counterclockwise direction. Upon de-energization of the solenoid 8I spring 85 forces th plunger 84 outwardly and the dog 93 becomes disengaged from the surface of the hoop 65, permitting the said dog and the roller 9I to resume their origina position as indicated in Fig. 6.

To prevent the hoop 65 from following along with the arm 60, in its return movement, another roller 95 and a dog 96 are employed. This roller and dog are pivoted on pintles 91 and 98 which are secured to the upright 58. The dog 96 has a cam surface 99, similar to the surface 94 of dog 93, which wedges against the inner surface of the hoop 65, preventing reverse movement of the hoop. Both the dog 93 and the dog 96 are designed so that the same are urged into engagement with the surface of the hoop 65 by gravity, although it can be readily comprehended that spring action may be used, if desired.

The ratchet wheel 59, previously referred to. has secured to it a pin IN. This pin is adapted to engage a hump I02, formed on one of the arms I03 of a leaf spring switch, indicated in its entirety by the reference numeral I04. This switch further includes another arm I05 and both of the arms I03 and I05 are provided with contacts I06 adapted to be brought into contact when the pin IOI engages the hump I02. The arms I03 and I05 are mounted on an insulating block I01 which is attached to the upright 56.

The operation of the form of the invention shown in Figs. 6, '1 and 8 is as follows: Heater 69 operates continuously and is connected to a source of electro-motive force. As the hoop 65 is heated the same bows outwardly and raises the lever H which closes the switch 16 and energizes the solenoid 8I. This draws the plunger 84 inwardly into said solenoid and the dog 93 and roller 9I move the hoop 65 circumferentially a distance sufficient to shift the deflected portion of the said hoop toward the left and to present a cool portion of the said hoop to the heater 69. This lowers the arm H and the switch 16 is opened and the solenoid 8| de-energized. Arm 60 is immediately returned to normal position through the action of spring 85 and the dog 96 and roller 95 prevent reverse movement of hoop 65 during such return movement of arm 60. As the arm 60 is being moved in a counter-clockwise direction, by means of the solenoid 8I, the dog 62 rotates ratchet wheel 59. As soon as the cycle is completed, the operation of the mechanism is repeated and the hoop 65 and the ratchet wheel 59 are further progressed. The operation of the device continues until the pin IOI travels completely around the circle and engages the hump I02. This closes switch I04. Switch I04 is connected to the particular circuit to be controlled by the device and in the case of an alarm would merely close the circuit containing the alarm and set off the alarm.

In Figs. 9 to 12 inclusive, I have shown a modification of my invention in which the thermally responsive member is constructed from a sheet of bi-metal in the form of an annulus. The invention is carried by a base I29 from which extends an upright I28.

The thermally responsive member of the form of the invention shown in Figs. 9 to 12 inclusive is indicated by the reference numeral I2I and as stated is in the form of an annulus which is concentrically disposed with reference to a horizontally positioned shaft I22. Shaft I22 is journaled in a bearing I20 formed on the upright I28. Rigidly secured to this shaft is a disc I23 which is formed with four lugs I24 extending outwardly therefrom. These lugs have shoulders I25 on which the annulus I2I rests and also have projections I26 which extend outwardly through slots I21 in the annulus I2I. These projections serve to form a drive between the annulus I2I and the shaft I22. The annulus I2I is thus caused to rotate in unison with the shaft I22 and at the same time is free to flex longitudinally with respect to said shaft when heat is applied to the same.

Pivoted to a boss I3I, on the upright I28 is an arm I32 which carries, at its outer end, a roller I33 which is journaled for rotation on a stud I34 secured to said arm. This roller is adapted to engage the outer surface of the annulus I2I and as the said annulus becomes flexed is adapted to move outwardly and swing the arm I32 in a counter-clockwise direction, as viewed in Fig. 11. A tension coil spring I35 hooked at one end to the arm I32 and at its other end to a pin I36, secured to upright I28, urges the roller I33 into engagement with the annulus I2I.

The disc I23 has issuing outwardly from it four teeth I31 which serve as stops for limiting the movement of the shaft I22. A catch I38, formed on the arm I32, is adapted to engage the stops I31 when the annulus I2I is cool, and arrests movement of the shaft I22 in a clockwise direction, as viewed in Fig. 10. When the annulus I2I is flexed through the application of heat thereto, roller I33 is forced outwardly and the lever I32 swung in a counter-clockwise direction, as viewed in Fig. 11 and the catch I38 disengaged from the stops I31.

For the purpose of heating the thermally responsive member I2I a hairpin heater I39 is employed. This heater is secured to an insulating block I4I (Fig. 10) which is mounted on a bracket I42 issuing outwardly from the upright I28. This heater is disposed in a recess I43 in the arm I32 and outwardly of the annulus I2I so that said annulus, when deflected, moves toward the heater. When the heater I39 is energized annulus I2I flexes in a direction toward the left, as viewed in Fig. 11, which disengages the catch I38 from the stops I31.

The shaft I22 is urged to rotate by means of a weight I44. This weight is attached to a cord I45 which is secured to and passes over a pulley or sheave I46 fast on the end of the shaft I22. When the shaft I22 is released through disengagement of the catch I38 with one of the stops I31, weight I44 causes rotation of said shaft and the same continues to rotate in a clockwise direction, as viewed in Fig. 10, until the catch I38 comes into engagement with another of, the stops I31.

Attached to the shaft I22, adjacent the sheave I46, is a spur pinion I41. This spur pinion meshes with a gear segment I48 which is pivoted on a stud I49 secured to the lowermost portion of the upright tact bar II which is adapted to connect two I28. The segment I48 carries a concontacts I52 together and to close a circuit through said contacts. These contacts and the contact bar I5I constitute a switch indicated in its entirety by the reference numeral I50. When the annulus I2I has traveled a sufficient amount, segment I48 is moved toward the right, as viewed in Fig. 9, until the contact bar I5I engages the contacts I52 and closes switch I50.

The operation of the form of the invention, shown in Figs. 9 to 12, is similar to that previously described. As the annulus I2I is heated the same flexes or bows in a direction forcing the roller I33 to the left, as viewed in Fig. 11, which disengages the catch I38 from the particular stop I31 with which the same has been in engagement. Weight I44 then causes rotation of shaft I22 which moves the flexed portion of the annulus away from the roller I33 and presents to it a cool portion of the said annulus. Such portion of the annulus, being not flexed, the catch I38 is immediately brought into position to engage the next stop I31 which comes into engagementwith it. The cycle is then repeated and continues until the contact bar I5I makes contacts with the contacts I 52 and closes switch I50. The device shown in Figs. 9 to 12 is manually reset by with-drawing roller I33 from engagement with annulus I2 I. This disengages the catch I38 from stop I31. The segment I48 may now be manually swung about the stud I49 and the cord I45 wound up and contact bar I5I separated from contacts I52. Upon release of the roller I33 the device is again ready to be used.

In the operation of all of the forms of my invention, a portion of the thermally responsive member is being heated to procure localized deflection thereof. At the same time all previously heated portions of the thermally responsive member are being cooled so that, after each deflection, a relatively cool portion of the thermally responsive member may be moved into position to be heated by the heater. This relative movement or succession of deflections is utilized to operate any time controlled or other appropriate device requiring a time greater than that procured by either the heating or cooling of the thermally responsive member during a single cycle. When the required number of cycles have been completed the mechanism is in condition to be immediately reset.

Where the invention is to be used for an electric toaster or other cooking device the switches shown would be opened upon the completion of the cycle of operation of the invention, instead of being closed. Similarly, the mechanically controlled device, shown in Figs. 1 to 5 inclusive, might be used to arrest the movement of a previously operating device, as well as to actuate or initiate movement thereof.

The advantages of my invention are manifest. An extremely simple construction is provided whereby timing of considerable extent may be procured. The device can be made to operate quietly and requires but a minimum force or effort to operate. My invention is particularly adaptable for use in conjunction with devices or mechanisms where electric current is available. By the use of proper gearing, timing of any duration may be procured and where the continuous thermally responsive member is utilized my invention will operate for an extremly great length of time, if desired. With my invention the timing is procured through the heating of the thermally responsive member which has long been recognized as producing more accurate timing than the cooling thereof so that far greater accuracy with my invention may be had than with devices where the cooling of the thermally responsive member from maximum temperature during the timing period is relied on for the timing. The individual heating periods are short and intense both of which facts tend towards accurate control. My invention can be constructed at a nominal expense and is simple in operation and practically fool proof.

Changes in the specific form of my invention, as herein disclosed, may be made within the scope of what is claimed without departing from the spirit of my invention.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

i. In a thermal timing mechanism, a thermally responsive member in the shape of a hoop, means for guiding said hoop for rotation about the axis thereof, a heater adapted to heat difierent portions of said hoop upon rotation thereof to procure localized deflections of said hoop at the portions thereof adjacent said heater and means actuated by said deflections for rotating said hoop an amount suflicient to present a relatively cool portion of the hoop to said heater.

2. In a thermal timing mechanism, a thermally responsive member comprising a strip of himetal, guide means for guiding said strip for movement in its direction of extent, heating means for heating a portion only of said thermally responsive member to cause localized deflection thereof, said heating means being fixed relative to said guide means, motive means for moving said thermally responsive member to subject different portions of said thermally responsive member to said heating means, during the cooling of previously heated portions thereof, and means operated by the deflections of said thermally responsive member for controlling the operation of said motive means to procure timed movement of said thermally responsive member.

3. In a thermal timing mechanism, a thermally responsive member mounted for movement in a predetermined direction, a stop device comprising stops movable with said thermally responsive member in the direction of movement thereof and stop means for engagement with said stops for arresting movement of said thermally responsive member, means urging movement of said thermally responsive member, a heater positioned to procure localized deflection of said thermally responsive member at each of a plurality of positions determined by said stop device, the deflections of said member intermittently rendering ineflective the engagement between said stop means and said stops to procure step-by-step movement of said thermally responsive member.

4. In a thermal timing mechanism, a thermally responsive member mounted for movement in a predetermined direction, a stop device comprising stops movable with said thermally responsive member in the direction of movement thereof and stop means for engagement with said stops for arresting movement of said thermally responsive member, means urging movement of said thermally responsive member, a heater positioned to procure deflection of said thermally responsive member at each of a plurality of positions determined by said stop device, the deflections of said member intermittently rendering ineffective the engagement between said stop means and said stops to procure step-by-step movement of said thermally responsive member,

and a time controlled device actuated by said member.

5. In a thermal timing mechanism, a thermally responsive member mounted for movement in a predetermined direction, a stop device comprising stop means movable with said thermally responsive member in the direction of movement thereof and other stop means for engagement with the first mentioned stop means for arresting movement of said thermally responsive mem ber, means urging movement of said thermally responsive member, a heater positioned to pro cure deflection of said thermally responsive member at each of a plurality of positions determined by said stop device, the deflections of said member intermittently rendering ineffective the engagement between the first mentioned stop means and the second mentioned stop means to procure step-by-step movement of said thermally responsive member, and a time controlled device actuated by said member.

6. In a thermal timing mechanism, a thermally responsive member, heating means for heating a number of portions of said thermally responsive member in succession, said portions of the thermally responsive member responding to the heat of the heating means, a movable member controlled by such responses of the thermally responsive member and motive means controlled by said movable member for shifting the heated portion of the thermally responsive member away from the heating means to subject other portions of the thermally responsive member to the action of the heating means.

7. In a thermal timing mechanism, a thermally responsive member, heating means for heating a number of portions of said thermally responsive member in succession, said portions of the thermally responsive member responding to the heat of the heating means, a movable member controlled by such responses of the thermally responsive member and motive means controlled by said movable member for controlling relative movement between the heating means and the thermally responsive member to procure heating of other portions of the thermally responsive member.

8. In a thermal timing mechanism, a thermally responsive member, means for guiding said thermally responsive member for movement in one direction, normally inactive motive means for moving said thermally responsive member in such direction, heating means for heating said thermally responsive member, said heating means causing movement of said thermally responsive member in another direction and means operated by movement of said thermally responsive member in the second direction for rendering said motive means active to procure movement of said thermally responsive member in the first direction.

9. In a thermal timing mechanism, a thermally responsive member, heating means for heating said thermally responsive member, means for supporting said thermally responsive member and said heating means for relative movement in one direction, normally inactive means for procuring relative movement between said thermally responsive member and heater in such direction, said heating means causing the thermally responsive member to move in another direction and means operated by such movement of said thermally responsive member for rendering said motive means active to procure relative movement between said thermally responsive member and said heating means in the first named direction.

10. In a thermal timing mechanism, a thermally responsive member mounted for movement in a predetermined direction, a stop device comprising stops movable with said thermally responsive member and stop means for engagement with said stops for arresting movement of said thermally responsiv member, means urging movement of said thermally responsive member, a heater positioned to procure localized deflection of said thermally responsive member at each of a plurality of positions determined by said stop device, the deflections of said member intermittently rendering ineffective the engagement between said stop means and said stops to procure step-by-step movement of said thermally re-- sponsive member.

11. In a thermal timing mechanism, a movable member, means for guiding said member for translatory movement, normally inactive motive means for moving said member in such direction, a thermally responsive member movable therewith, means for heating localized portions of said thermally responsive member in succession to procure localized deflections thereof, and means controlled by the successive deflections of said thermally responsive member for rendering said motive means active to control the movement of said movable member.

12. In a thermal timing mechanism, a thermally responsive member, means for guiding said member for translatory movement, means for heating localized portions of said thermally responsive member in succession to procure localized deflections thereof and means controlled by the successive deflections of said thermally responsive member for controlling its translatory movement.

13. In a thermal timing mechanism, a thermally responsive member having means for guiding said member for translator-y movement, means for successively heating localized portions of said thermally responsive member to procure localized deflections thereof, a rotary member traveling in conjunction with said thermally responsive member and controlling the translatory movement thereof and means controlled by the successive deflections of said thermally responsive member for controlling the movement of said rotary member.

14. In a thermally responsive member, a rack, means for guiding said rack for translatory movement, a pinion meshing with said rack, means for journaling said pinion for rotation, a thermally responsive member movable with said rack, heating means for heating localized portions of said thermally responsive member in succession to procure localized deflections thereof and means controlled by the successive deflections of said thermally responsive member for controlling the movement of said pinion.

15. In a thermal timing mechanism, a strip of bi-metal formed with a number of spaced openings therein providing shoulders forming a rack, means for guiding said strip for movement in the direction of its length, a pinion meshing with said rack, heating means for successively heating localized portions of said bimetal to procure localized deflections thereof and means controlled by the successive deflections of said bi-metal for controlling the movement of said pinion.

16. In a thermal timing mechanism, a thermally responsive member, means for guidin said thermally responsive member for movement in a certain direction, a movable member movable with said thermally responsive member, separate guide means for guiding said second named member for movement, heating means for heating localized portions of said thermally responsive member in succession to procure localized deflections thereof, means for yieldingly urging movement of said thermally responsive member and said movable member, stop means for controlling the movement of said movable member, said stop means including two relatively slidable parts, one of said parts being operated by said movable member and means operated by the successive deflections of said thermally responsive member for actuating said stop means.

17. In a thermal timing mechanism, a thermally responsive member, means for guiding said thermally responsive member for movement in a certain direction, heating means for successively heating localized portions of said thermally responsive member to procure localized deflections thereof, means for yieldingly urging movement of said thermally responsive member, stop means for controlling the movement of said thermally responsive member, said stop means including two relatively slidable parts, said parts being disposed in retarded heat-conducting relation with respect to said heater and thermally responsive member to prevent heating thereof and means operated by the successive deflections of said thermally responsive member for actuating said stop means.

18. In a thermal timing mechanism, a thermally responsive member arranged in the form of a circle, normally inactive motive means for moving said member in the direction of its circumference, means for successively heating different circumferentially arranged portions thereof to procure localized deflections thereof, a movable member adapted to render said motive means active and means controlled by the successive deflections of said thermally responsive member for controlling the movement of said movable member.

19. In a thermal timing mechanism, a thermally responsive member in the shape of a hoop, normally inactive motive means for moving said member in the direction of its extent, means for successively heating portions of said member to procure localized deflections thereof, a movable member adapted to render said motive means active and means controlled by said deflections for controlling the movement of said movable member.

20. In a thermal timing mechanism, a thermallyresponsive member in the shape of a hoop, means for guiding said hoop for rotation about the axis thereof, a heater adapted to heat different portions of said hoop upon rotation thereof to procure localized deflections of said hoop at the portions thereof adjacent said heater and means responsive to said deflections for causing rotation of said hoop.

21. In a thermal timing mechanism, a thermally responsive member in the shape of a hoop, means for guiding said hoop for rotation about the axis thereof, a heater adapted to heat different portions of said hoop upon rotation thereof to procure localized deflections of said hoop at the portions thereof adjacent said heater, a movable member, and means controlled by said deflections for controlling the movement of said movable member.

22. In a thermal timing mechanism, a thermally responsive member in the form of a disc guided for rotational movement about the axis thereof, a heater for successively heating different portions of said member situated about the periphery thereof to procure localized deflections of said member and means responsive to the successive deflections of said member for causing rotation thereof.

23. In a thermal timing mechanism, a thermally responsive member in the form of a disc, heating means for successively heating different portions of said member situated about the periphery thereof to procure localized deflections of said member, a movable member, and means controlled by said deflections for controlling the movement of said movable member.

24. In a thermal timing mechanism, a thermally responsive sheet-like member, guide means for guiding said member for movement along a path contained substantially in the surface of said member, heating means for heating said thermally responsive member, said heating means being fixed relative to said guide means to cause different portions of the thermally responsive member to become heated upon movement of said thermally responsive member relative to the guide means to produce localized deflections of the thermally responsive member, motive means for moving said thermally responsive member to subject different portions of said thermally responsive member to said heating means during the cooling of previously heated portions thereof and means operated by the deflections of said thermally responsive member for controlling the operation of said motive means.

25. In a thermal timing mechanism, a heater, a bi-metal strip mounted for lengthwise movement to successively bring adjacent portions thereof into position to be locally heated and deflected by said heater and having a lengthwise row of perforations, a rotatable member having teeth engaging said perforations, whereby such member rotates and said strip moves lengthwise concurrently, a spring for urging such movement of the strip and rotatable member, a second toothed member mounted for rotation coaxially and simultaneously with said rotatable member, and pivoted latch means to engage the teeth of said second tooth member to hold said rotatable member and strip stationary against the action of said spring, said latch means including an element bearing on the bi-metal strip in the region thereof subject to heating by said heater, whereby said latch means is moved to disengage from the teeth of the second toothed member in response to successive deflections of the bi-metal strip.

26. In a thermal timing mechanism, a thermally responsive member, heating means for heating a number of portions of said thermally responsive member in succession, said portions of the thermally responsive member responding to the heat of the heating means, motive means tending to urge relative movement between the thermally responsive member and the heating means to subject other portions of the thermally responsive member to the action of the heating means, restraining means for restraining such relative movement, said thermally responsive member, upon a response to the heat delivered by the heating means releasing said restraining means to cause relative movement between said i i i 3 i i procuring relative movement between said thermally responsive member and the hot spot of the heating means to procure heating of a number of portions of said thermally responsive member, and means responsive to the action of the thermally responsive member upon the heating thereof, said means rendering said shifting means active.

ROBERT SARDESON. 

